Data-processing induced GPS-positioning error

:Global Positioning System data processing is affected by many non-tectonic factors, including the common-mode errors (CME) in station-position time series. The characteristics and origins of CME are still not clear, due to uneven distribution of global CPS networks and the lack of reliable data of the position time series. In this work, data from 241 continuous CPS stations were reprocessed in a consistent way and the results were compared with those generated at Jet Propulsion Laboratory (JPL). Improvements of residual positions were obtained for many low-quality stations, especially those located in Asia and Australia. Key words: GPS; position time series; reprocessing; non-tectonic; common-mode error